Effect of processing on dietary fiber content of cereals and pulses

Total dietary fiber (TDF), insoluble dietary fiber (IDF) and soluble dietary fiber (SDF) content of rice, wheat, sorghum, maize, ragi, bajra, whole grains of pigeonpea, chickpea, green gram and lentil as well as their dehusked split dhals were analyzed. Cereals except rice flours were made into chapati (unleavened bread), while rice and dhals were cooked in a pressure cooker. After the processing, IDF and SDF contents of these foods were also analyzed. Among the cereals, rice had the lowest TDF (4.1%) and wheat had the highest (12.5%). TDF content of whole pulses ranged from 15.8% in lentil to 28.3% in chickpea. IDF as % of TDF constituted 85 to 89% in whole pulses. Dehusking of pulses into dhals decreased TDF and IDF contents significantly. Among the dhals, green gram dhal had the lowest (8.2%, 6.5%) and chickpea dhal (15.3%, 12.7%) had the highest TDF and IDF contents, respectively. Processing of cereals had no effect on their TDF and IDF contents, with the exception of ragi, where a significant increase in TDF and IDF was observed. Cooking of dhals brought about a significant increase in their TDF and IDF contents.